1. Field of the Invention
The present invention relates to a flexible printed circuit board (FPCB) and a manufacturing method thereof, and more particularly, to an FPCB used in various electrical and/or electronic devices such as a mobile communication device and a method of manufacturing the same.
2. Description of the Related Art
In general, an FPCB is a circuit board that is designed to conduct various complicated signals, and includes a conductor layer for conducting electrical signals and dielectric layers covering the top surface and the underside surface of the conductive layer. This type of FPCB can be manufactured to be thin and small, and is used for a thin and small electrical device such as a mobile communication device.
The FPCB has highly-flexible physical property, and thus is used for a shape-changeable electrical device. Particularly, the FPCB is used for electrical circuit connection between a body and a slide (or a foldable member) in a slide-type or folder-type mobile communication device.
That is, when the slide (or the foldable member) is moved open or closed, the FPCB flexibly bends, so that the circuit can be continuously connected.
As mentioned above, the FPCB maintains electrical circuit connection when it repeats bending since it is used in a shape-changeable device such as a mobile communication device.
However, when the FPCB is repeatedly bending, a conductor layer inside the FPCB suffers from fatigue, caused by the repeated bending. This as a result causes cracks in the conductor layer, thereby reducing the lifetime of the FPCB.